It is known to surround sausage with an encasing netting which is extendible in the longitudinal direction because of its tied or knitted structure. This is originally intended to relieve the sausage casing of the filling pressure. It nowadays assumes more and more a decorative character. It is therefore used not only for types of sausage which shrink in a ripening process and from which it can therefore easily be removed later, but also for fresh sausage. When, in the latter case, the encasing netting is cut lengthways so that it can be removed, the sausage surface is also unavoidably cut into, this being undesirable. It is known, admittedly, to provide stitched sausage casings with a tear-open thread within the seam (DE-U-7807929, DE-A-3725263, DE-A-2811340, DE-A-3127444). However, encasing nettings are tied or knitted seamlessly as a tube, so that a longitudinal seam, into which a tear-open thread could be inserted, is not available there. They are also produced continuously, and therefore the tear-open thread is bound over its entire length into the encasing netting and there is no projecting end at which it could be grasped.